Ratio Calculator
Enter three values and get the fourth.
Inputs
Results
D
12
Formula
D = B × C ÷ A.
Example
2:3 = 8:? → 12.
What the Ratio Calculator does
The Ratio Calculator handles the exact ratio math you learned in school, but instantly and without arithmetic mistakes. It's useful for homework checking, day-to-day conversions, and quick sanity checks.
How to use it
Fill in the fields you know and the Ratio Calculator solves for the missing one. Every result is labeled clearly, so it's obvious what you're looking at.
Frequently asked questions